1. Field of the Invention
The present invention relates to a gearshift device for an automotive automatic transmission.
2. Description of Related Art
There have widely been known transmission control devices for automotive vehicles that operates an automatic transmission selectively in two gearshift modes, namely an automatic gearshift mode and a manual gearshift mode, according to driver's preference or driving circumstances. The automatic gearshift mode is the mode in which the automatic transmission is automatically varied in gear ratio according to a driving conditions including an engine loading and a vehicle speed. The manual gearshift mode is the mode in which the automatic transmission is shifted up or down one gear step by step by operating a manual gearshift device such as comprising gearshift switches.
A variety of manual gearshift devices are known in the art. One example of such a manual gearshift device that is disclosed in Japanese Unexamined Patent Publication No. 6-17911 comprises two gearshift switches installed on one of spokes of a steering wheel, namely a shift-up switch for providing a transmission control apparatus with a shift-up command signal and a shift-down switch for providing the transmission control apparatus with a shift-down command signal. This type of manual gearshift device enables the driver to operate the shift-up switch or the shift-down switch without taking his or her hand off from the steering wheel, so as to provide operational facility.
However, the prior art manual gearshift device for an automatic transmission is often accompanied by the fear of causing a gearshift in an unintended direction resulting from touching one of these shift-up switch and shift-down switch in mistake for another. Such a wrong operation is brought about due to an arrangement of these shift-up switch and shift-down switch in proximity to each other on a same spoke of the steering wheel.